Typewriting-machine



F. HOFFMANN.

TYPEWRITING MACHINE.

APPLICATION FILED AuG.3. 1920.

F. HOFFMANN. TYPEWRITING MACHINE. APPLICATION FILED AUG.3. |920.

1,3705648, Patented Mar. 8, 1921.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

TYPEWRITING-MACHINE.

Specification of Letters Patent.

Patented lifar. 8. 1921.

Application led August 3, 1920. Serial No. 401,074.

T0 all whom t may concern Be it known that T, FERDINAND HOFF- MANN, a citizen of the German Republic, and resident of Cuchenheim, at Euskirchen, Germany, have invented certain new and useful Improvements in rlypewriting-Wlachines, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to certain new and useful improvements in typewriters.

Typewriters of small'size, so constructed that their writing surface serves as a base to the body for receiving the pressure and for the transport are-already known. Such typewriters are generally of the typewheel pattern.

Heretofore typewriters of this class, have been diflicult to operate particularly because different manipulations were necessary for setting and for printing. According to the present invention both the setting of the typewheel and the printing are effected by means of a rocking and radially shiftable yoke, which is fitted to the outside of the casing inclosing the typewheel. Thereby the operation is greatly simplified. The said yoke is, furthermore, employed for operating a ratchet gear which effects the movement of the typewriter and the feed of the ribbon. Through the hollowv yoke is carried a cord, which serves to bring a different row of type into printing line. The yoke which serves for setting the typewheel and for printing,`is thus utilized in a very simple manner, for effecting the other operations. T he small typewriter may be made in the form of a small box with a yoke, which may be easily carried about.

Figure l is a substantially central cross section through the casing.

Fig. 2 is a side elevation.

Fig. 3 is a front elevation.

Fig. 4l is a rear elevation, broken off.

Fig. 5 is a plan view, also broken off.

Fig. 6 is a sectional view along the line 6, 6 in Fig. l.

Typewriters according to the present invention belong to that class of typewriters in which, by turning the typewheel, the respective letter to be printed is brought into printing position whereupon it is printed on the paper by the said typewheel being pressed against the latter, and the impression made by an ink ribbon passing between the type and the paper.

ln the present typewriter the typewheel is axially shiftable, so as to bring different rows of type, containing capitals, small letters, figures and the like to the printing level.

The typewheel e is fitted on the hollow axis b, which is so journaled in its casing, that it may be forced downward against the action of the springs d. To the ends of the axis b is attached a yoke f which may be swung back and 'forth by mea-ns of a handle g. By the rocking of the yoke f, which is limited by stops, the sectional gear wheel L is rotated by means of a slot and pin gear,

so that by the aid yof a further gear wheel the typewheel a. is likewise rotated. A pointer attached to the handle g plays over a dial z', thus allowing 'of turning the typewheel to bring into proper position the rew spective letter to be printed. By pressure on the handle g the typewheel is lowered, the said pointer therewith entering into a small notch provided at each character on the dial, see Fig. 5. When the typewheel is thus lowered the respective type reaches the printing point, over` the ink ribbon 7s. The handle g is shiftable in the hollow yoke f, see Fig. l. lt is coupled by means of a cord m with a central extension of the type' wheel protruding into the hollow axis b, so that by moving the said handwhe'el g the typewheel can he shifted on the hollow axis Z2. By this means a different row of types can be brought into printing level. The typewheel is moved-step by step, by the said extension, when the axis Z) turns, but the axis is not shifted with the typewheel.

The ink ribbon la is wound around the middle 0f a drum a, which revolves loosely around the periphery of the type-wheel, see Fig. l. The cylindrical part of this drum is formed by wires o, which are slightly bent inwardly in the middle so as to orm a recess for receiving the ribbon, see Fig. 1. When a letter has been printed and the pressure on the handle is released, the yoke f with the aXis b and the type-wheel a will be raised again through the medium of the springs al, while the drum n remains always at its same level. a is a ratchet gear and fo the pawl, coperating therewith, see Fig. 4. This pawl p acts during its return stroke, z'. e. on rising of the yoke f, in such a manner that the drum n is turned one notch with the ribbon lo. Thereby not only the required feed of the ribbon but also the adchanged.

vancement ot the whole typewriter by one notch or space is obtained. rhis is obtain-A able by reason of the fact that the whole body or' the typewriter rests on the paper to be printed, and is held by a handle of the horizontal yoke g, carrying a stand er Sup port 7 adapted to bear on the paper.

The operation is such that by the respective adjustment of the rocking yoke ,t thedesired type can be brought in front of the printing point, whereupon the type isV printed by the pressure on the said yoke with one hand, while the other hand of the operator holds the yoke g and gives the typewriter its proper position. then,the

pressure on the lever 7- is released, the whole typewriter will be advanced by a` given dis-- tance, viz., the pitch of the characters. While the typewriter is thus aevanced, the yoke g should not be held tight, but the same should be heid very loosely and it should employed only for directing the typewriter in a straight line, if the same lshould have gone out oi linea The toot fr is preferably made of a transparent material, such as Celluloid or the like, so that the printing may be seen through it, and the proper travel of the typewriter be observed.y

In order that the pressure be transf-erred downwardly even whenV the yoke is in a slanting position, stays o, 'u are fitted to the yoke f see Fig. Al, For the same purpose an vthe respective character, a ratchet gear operated by the yoke on its upward movement, and a drum for carrying an ink ribbon, said drum adapted to be actuated by said ratchet gear and advanced one space at each actuation. p Y

2. in a typewriter in which the writing surface serves as a brace for the body of the machine and for the advance the latter', a yoke displaceably fitted to the outside or the type wheel casing and adapted to seat the type wheeland print the respective char acter, a ratchet gear operated by the yoke on its upward movement, a drum for carrying an ink ribbon, said drum adapted to be enacted byr said, ratchet gear Y and advanced one space at, each actuation, a type wheel having a plurality or' rolls oi characters and axially shiitable, vand cord coupling, said type wheelV with the printing yoke, said yoke being hollow and the type wheel axis also being hollow, said cord beingpassed through said axis and yoke.

3. In a typewriter in which the writing surface serves as a base for the body oi the machine and for the advance of the latter, type wheel, a hollow axis therefor, a yoke mounted on saidaXis for rocking movement, means whereby the rocking of said yoke rotates the type wheel, a handle shittable in said yoke, and Yacrd passed through said yoke and connected with said type wheel so that movement on said handle shifts the type-wheel on its axis. f Y

In testimony whereofl aiix my signature y in the presence of two witnesses.

FERDINAND HOFFMANN. Witnesses: V

LUDWIG HAMMERSEN, PAUL MLLor.` 

